Introduction
Welcome back! In our last session, you built a crucial tool: a five-step value scale. You learned to control your pencil to create five distinct, evenly-spaced tones from pure white to solid black. This exercise was about building a reliable, repeatable "palette" of values.
Today, we put that palette to work. The goal of this lesson is to map the primary shadow shapes onto basic 3D forms (sphere, cube, and cylinder).
You've already learned to deconstruct complex objects into these fundamental forms, and you know the "anatomy" of a shadow (core shadow, cast shadow, etc.). Now, we will combine these skills. You will learn to see shading not as random blending, but as a logical process of identifying specific shadow shapes and filling them with the specific values from the scale you just created. This systematic approach—identifying shapes, then assigning properties—should feel quite structured.
The Two Families: Light and Shadow
Before we start shading, let's establish a powerful mental model. Instead of thinking of a long, continuous gradient from light to dark, it's more effective to first divide everything you see into two distinct groups: the light family and the shadow family.
Everything on an object that is facing the light source belongs to the light family. Everything turned away from the light belongs to the shadow family. The dividing line between these two is called the Terminator.
Let's watch a video from Proko that explains this concept clearly.
Go From Flat to Realistic Shading! Here’s How
This video, "Go From Flat to Realistic Shading! Here’s How," introduces the foundational concept of separating values into light and shadow families. This is the 'why' behind organized shading.
Watch from 00:53 to 02:07. Focus on understanding the difference between the 'light family' and the 'shadow family' and the idea that every change in value suggests a change in the plane of the object.
This initial separation of light from shadow is the single most important step in creating a convincing illusion of form.
The Anatomy of Shadow on Different Forms
Now that we have our two families, let's zoom in and identify the specific parts of a shadow you learned about in a previous lesson. We'll look at how they appear on our three basic forms.
Notice the key differences between the forms:
- On the Sphere (a curved form): The transition from light to shadow is gradual. The core shadow appears as a soft-edged band that follows the curve of the sphere.
- On the Cube (a planar form): The transitions are sharp. Each face, or plane, of the cube catches the light at a different angle, so each face will be a single, flat value. There are no smooth gradients on the faces themselves.
- On the Cylinder (a mixed form): This form combines both behaviors. The flat top acts like a face of the cube, receiving a flat area of light. The curved body acts like the sphere, showing a gradual transition from light to shadow.
A System for Mapping Values
So, how do we connect the shadow shapes to the 5-step value scale you created? We can use a simple, logical system.
Let's return to the Proko video, which now breaks down the light and shadow families into a five-value structure that maps perfectly to our scale.
Go From Flat to Realistic Shading! Here’s How
The same Proko video will now show you a practical system for assigning values to the different parts of the light and shadow families.
Watch from 02:20 to 06:15. First, pay attention to the names of the different zones (Terminator, Form Shadow, Center Light, etc.). Then, focus on how he groups these zones into a five-value system: three values for the light family and two for the shadow family. This gives you a clear recipe for shading.
Here's how we can map this system to the 5-step value scale you already made:
| Value on Your Scale | Proko's Zone | Description |
|---|---|---|
| 1 (White) | Highlight | The direct reflection of the light source. |
| 2 (Light Gray) | Light Halftone | The area of the object directly facing the light. |
| 3 (Mid Gray) | Dark Halftone | The area turning away from the light, near the shadow line. |
| 4 (Dark Gray) | Core Shadow | The darkest part of the shadow on the object itself. |
| 5 (Black) | Occlusion/Cast Shadow | The darkest areas, where light is blocked entirely. |
Note: Reflected light is also a key component. It's a part of the shadow family, but it's lighter than the core shadow—often around a Value 3 or 4. For now, focus on mapping the core shadow and cast shadow first.
Practice: Shading the Basic Forms (35 minutes)
Now it's time to put all this theory into practice. Your task is to draw and shade a sphere, a cube, and a cylinder.
Your Setup:
- A page in your sketchbook for each form.
- Your drawing pencils (HB for layout, 2B or 4B for shading).
- Your 5-step value scale from the last lesson. Keep it next to you as a reference.
For a guided walkthrough of the shading process for each form, I recommend this video. You can follow along with it.
How to Shade Basic Forms - Pencil Tutorial
The video "How to Shade Basic Forms" by The Virtual Instructor provides a clear, real-time demonstration of shading each of the basic forms. Use this as your guide during the practice session.
The video demonstrates shading several forms. Focus on these parts: Sphere: (01:37 - 02:32) Cube: (02:32 - 04:18) Cylinder: (05:46 - 07:08) For each form, pause the video and follow the steps on your own paper.
The Process (The "Algorithm"):
- Draw the Form: Lightly sketch the outline of a sphere, cube, or cylinder using an HB pencil.
- Establish the Light Source: Make a small arrow in the corner of your page to remind yourself where the light is coming from (e.g., top-left).
- Map the Shadow Shapes: With your HB pencil, lightly draw the outline of the core shadow on the form and the outline of the cast shadow on the ground. This is the most critical step—you are creating a map before you start coloring it in.
- For the sphere and cylinder, this will be a curved, soft-edged shape.
- For the cube, this will be an entire plane.
- Fill the Shapes with Value:
- Using your 2B or 4B pencil, fill in your darkest areas first: the cast shadow and core shadow (Value 4-5).
- Next, fill in the mid-tones (Value 2-3).
- On the sphere and cylinder, make sure to add a small area of reflected light (Value 3) on the side of the form shadow opposite the core shadow.
- Leave the highlight as the pure white of the paper (Value 1).
- Refine and Compare: Use your value scale to check your work. Does your core shadow match Value 4? Is your mid-tone a clear Value 2? Adjust as needed.
Spend about 10-12 minutes on each form. Don't worry about perfection. Focus on the process: Map the shapes first, then fill them with distinct values.
For an alternative text-and-image-based guide, you can refer to this article.
How to Shade Basic 3D Shapes Tutorial
The article "How to Shade Basic 3D Shapes Tutorial" from EasyDrawingTips provides another clear, step-by-step breakdown for shading each form, which can be a useful reference if you prefer reading.
Review the sections "How to Shade a Cube," "How to Shade a Sphere," and "How to Shade a Cylinder." Notice how the author discusses the direction of shading strokes to help emphasize the form.
Conclusion
Excellent work today. You've made a significant leap from just understanding values to actively using them to construct three-dimensional form. By treating shading as a process of mapping shapes, you're building a powerful and repeatable skill.
Key Takeaways:
- Shading becomes logical when you first divide a form into a light family and a shadow family.
- The boundary between light and shadow is the Terminator. It's soft on curved surfaces and sharp on planar ones.
- Basic forms react to light differently: cubes have flat planes of value, while spheres and cylinders have smooth gradations.
- Your 5-step value scale provides a "palette" to systematically assign values to the different zones of light and shadow.
- The process is key: Draw the form -> Define the light source -> Map the shadow shapes -> Fill with value.
In our next lesson, we will dig deeper into how light interacts with planes. We will analyze exactly how the angle of a surface relative to the light source affects its value, building directly on what you observed today while shading the cube.